I expect the altered will face discrimination, at least at first, especially if it upsets the religious and it surely will. It could take some time before it would be the 'altered' that dominate and discriminate against 'normals'.
I did watch Gattaca and note that it played to the fears of 'normal' people being supplanted; us normals sympathise with the very capable but genetically flawed main character.
In SF writing especially, it's a recurring theme, sometimes from the perspective of 'normals', sometimes from the perspective of 'altereds' and sometimes both. Mostly they don't really add that much insight but occaisionally can be both a good read and cover some of the issues and dilemmas. Not much on my bookshelf right now but there is one with such a theme called 'Blueheart' by Alison Sinclair. Not a well known author but I thought worth reading both for looking at the tensions between 'adaptives' seeking to make their one-off adaptations to a water world into 'germ line' changes that would be passed to their children as well as some of the issues surrounding supplanting an existing ecosystem with 'suitable' life. What's improbable is facing those issues so far away in both space and time; the dilemmas are upon us right here and now.